Plug body for medical fluid container

ABSTRACT

A plug body for chemical container capable of preventing the contact thereof with chemical and preventing ruptured film from falling into the chemical, comprising a valve ( 1 ) having an insert hole ( 3 ) formed at the center thereof, a cover ( 2 ) for holding the valve ( 1 ) by covering at least the upper peripheral edge of the valve ( 1 ), and a locking means for locking an insert body to the cover ( 2 ) by using the edge part of the cover ( 2 ) having a fitting hole formed therein when the insert body is inserted into the insert hole ( 3 ), wherein the rear surface peripheral part of the valve ( 1 ) is held by a pedestal part ( 5 ), and a film ( 4 ) covering the rear surface of the valve is disposed on the upper surface of the pedestal part ( 5 ).

TECHNICAL FIELD

The present invention relates to plug bodies for medical fluidcontainers filled with liquids. In particular, it relates to medicalfluid container plug bodies that are used in conjunction with insertionbodies that have obtuse tips.

BACKGROUND ART

Generally, for anticancer drugs, antibiotics, blood products, andlyophilized preparations that are put into containers such as medicalfluid bags or vials and the like, there are the problems of poorstability and reduced medicinal efficacy when these products are storedin liquid form. For these reasons, medical institutions such ashospitals have conventionally dealt with this by liquefying thesepreparations immediately before use, and using them in such ways asintravenous drips. The tasks required to perform this conventionallyhave involved filling a syringe fitted with a sharp needle with asolution or the like, then thrusting the needle into the rubber plugbody of a medicine bag or similar.

Furthermore, when mixing different medical fluids from a three-waystopcock fitted in the middle of a solution-feeding line of an infusionor blood transfusion kit, or, conversely, when collecting medicalfluids, or similar, while performing an infusion or blood transfusionfor a patient, there are always the tasks of detaching and attachingneedles to the main body of the syringe, and using sharp needles forthis is accompanied with the risks of accidental needle jabs and medicalfluid contamination.

Moreover, synthetic rubbers such as isoprene rubber are used for almostall the plug bodies for these medical fluids, and contact between theseand the medical fluids can cause problems of medical fluid contaminationdue to the elution of additives, so that contact between the plug andthe medical fluid is currently avoided by providing a plastic filmbetween these plug bodies and medical fluids. Further, conceivablemethods for providing these plastic films include, for example, methodsin which fluorine-based resins or the like are laminated on the surfacethat comes in contact with the medical fluid.

Various contrivances are used in ways intended to solve these problems,such as using adapters or communicating devices such as linking tubes toconnect syringes fitted with obtuse cannulas to vials or the like, andthen infusing or drawing out the medical fluids.

For example, PCT (WO) H3-504571 (1991) discloses mainly a slittedinfusion area into which an obtuse cannula can be inserted repeatedly.

Furthermore, JP H7-75663A (1995) discloses mainly a method of preventingmedical fluid contact by applying film to a slitted plug body. Further,at the opening of the container, a rubber plug body is used that isprovided with a pre-perforated penetration hole, with this penetrationhole enabling approximately 1-mm diameter metal needles to pass throughthe rubber plug body, and being small enough not to be easilydistinguished from the surface by the naked eye. When not yet puncturedby a cannula, the plug stays in a blocking condition due to self-sealingof the rubber, and when punctured by a cannula, the surface of thepunctured hole adheres to the outer periphery of the cannula due toself-sealing of the rubber.

However, in the method disclosed in PCT (WO) 3-504571 (1991), aspecial-purpose cannula is necessary in order to allow insertion throughthe sealing materials. Further, there is no mention of the possibilityof using ordinary syringes. Therefore, for infusion or blood transfusionkits requiring three-way mixed injection openings, there exists thepotential problem of being unable to perform mixing injections.

Moreover, as no measures are implemented in regard to medical fluidcontact, the issue of avoiding contact between the plug body and themedical fluids is unresolved.

On the other hand, JP H7-75663A (1995) has the problem that, althoughsuitable for the insertion of needles with comparatively sharp ends, itis unsuitable for insertion bodies with a flat-surface end such as asyringe luer connector. This is because a large penetration resistanceis required to pass through the film at the time of insertion.

Furthermore, there is also the problem that, although the pore surfacecan adhere to the outer periphery of the cannula due to theself-adhesiveness of the rubber, it is difficult to ensure that insertedcannulas can be maintained stably without wobbling movements.

Moreover, there is no consistency in the way the film ruptures wheninsertion bodies are inserted, which entails the risk, depending on theway it ruptures, of pieces of ruptured film falling into the medicalfluids and causing contamination of the medical fluids.

It is an object of the present invention to solve the problems above byproviding a plug body for a medical fluid container, with which contactbetween plugs and medical fluids can be prevented, and that can be usedwith insertion bodies with obtuse tips.

DISCLOSURE OF INVENTION

In order to achieve the objective stated above, a plug body for amedical fluid container of the present invention includes a disk-shapedvalve provided with an insertion hole in its central portion; and acover that fixedly supports the valve, covering at least the valve'supper periphery; wherein a lower periphery of the valve's rear surfaceis supported by a pedestal portion, a film covering the rear surface ofthe valve is arranged on an upper surface of the pedestal portion, andthe film can be pressed through by an insertion member with an obtusetip; and wherein a front surface of the valve has a ring-shaped notchportion, which, upon insertion of the insertion member with an obtusetip, causes the valve to be sectioned into a portion that is fixed and aportion that expands.

With this structure, in addition to being able to securely fasten thevalve between the cover and the pedestal portion, it is possible toprevent contact between the valve and the medical fluids, and it ispossible for the film to be passed through with low penetrationresistance, even when using insertion bodies with obtuse tips, of whichsyringe luer connectors are typical.

Furthermore, it is preferable for the plug body for medical fluidcontainers of the present invention to have a locking means to lock aninsertion member to the plug body using the outer edge of the cover,which is provided with a fitting hole for when an insertion member isinserted into the insertion hole. In addition to allowing easy andreliable interlocking for insertion bodies with obtuse tips, of whichsyringe luer connectors are typical, this also can prevent contactbetween the plug body and medical fluids.

Furthermore, it is preferable for the outer portion of the upper surfaceof the pedestal portion of the plug body for medical fluid containers ofthe present invention to be beveled. As this reduces the pressureasserted on the border between the heat-sealed areas of the film and theother areas, due to obtuse angle contact with the pedestal portion whenan insertion member is inserted, this reduces the likelihood of piecesof film tearing away from the border area and falling as fragments ofruptured film.

Furthermore, for the plug body for medical fluid containers of thepresent invention, it is preferable for the penetration resistance forwhen an insertion member with an obtuse tip is thrust into the film tobe no more than 30 Newtons. This is because this enables the film to beeasily broken by pressure applied to it by the obtuse tip of aninsertion member, of which syringe luer connectors are typical.

Furthermore, for the film of the plug body for medical fluid containersof the present invention, it is preferable for this to be a layered filmincluding a film provided with a multitude of pass-through pores andfilm with no micro-holes. Also, for the film of the plug body formedical fluid containers of the present invention, it is also suitablefor this to be a film provided with a multitude of non-pass-throughpores. Further, it also could be a film provided with slits that do notpass through the film. Those enable easy rupturing of the film, even forinsertion bodies with obtuse tips such as luer connectors.

Furthermore, it is preferable for the film of the plug body for medicalfluid containers of the present invention to tear linearly when torn byan insertion member. This makes it difficult for pieces of film to tearaway and fall from the pedestal portion.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a top plan view of the plug body for medical fluid containersof the present invention.

FIG. 2 is a cross sectional view of the plug body for medical fluidcontainers of the present invention.

FIG. 3A is a bottom view of the lock adapter, FIG. 3B is a sidecross-sectional view of the lock adapter of the plug body for medicalfluid containers of the present invention; and FIG. 3C is a side view ofthe lock adapter of the plug body for medical fluid containers of thepresent invention.

FIG. 4 is an enlarged cross-sectional view of the lower part of the lockadapter of the plug body for medical fluid containers of the presentinvention.

FIG. 5A shows the condition immediately before connection of the lockadapter cover, and FIG. 5B shows the condition immediately afterconnection of the lock adapter cover.

FIG. 6A is a top plan view of the valve for the medical fluid containerplug body for the present invention, and FIG. 6B is a cross-sectionalview of the valve for the medical fluid container plug body for thepresent invention.

FIG. 7A is a bottom view of the cover for the medical fluid containerplug body for the present invention, and FIG. 7B is a cross-sectionalview of the cover for the medical fluid container plug body for thepresent invention.

FIGS. 8A to 8C are explanatory diagrams of the film for the medicalfluid container plug body for the present invention.

FIG. 9 is a cross-sectional view of the pedestal portion for the medicalfluid container plug body for the present invention.

FIG. 10 is an explanatory diagram of film rupture for the medical fluidcontainer plug body for the present invention.

FIG. 11 is an explanatory diagram of a method for confirming theoccurrence of foreign matter in regard to the medical fluid containerplug body for the present invention.

FIG. 12 is an explanatory diagram of a method for confirming theoccurrence of foreign matter in regard to the medical fluid containerplug body for the present invention.

FIG. 13 is an explanatory diagram of a method for welding a cover and apedestal portion in regard to the medical fluid container plug body forthe present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention are explained in the following,referring to the accompanying drawings.

First, a plug body for medical fluid containers according to anembodiment of the present invention mainly includes a valve to open andclose the flow channel, a cover to fixedly support that valve, a meansfor locking an insertion member such as a syringe luer connector,provided in the cover, and a film to cover the rear side of the valve.These structural elements are explained below.

As long as the cover is sturdy enough to hold (fixedly support) thevalve when the insertion member is inserted into or extracted from thevalve, there is no particular limitation to it. For example, as shown inFIG. 1 and FIG. 2, if a cover 2 is provided so that the center area ofthe front surface of a valve 1 is left open (exposed) and is at leastcovering the upper periphery of the valve 1, it will be easier to findthe insertion position for the insertion member, and contamination ofthe valve surface due to accidental contact can be prevented. Bettereffectiveness can also be achieved by providing a gentle taper (slant)to the front side of the cover 2.

There is no particular limitation to the outward form of the apertureportion of the plug bodies for medical fluid containers according toembodiments of the present invention, as long as the valve 1 can besupported fixedly by covering it with the cover 2. However, in orderthat valve 1 can be firmly fastened in its prescribed position in theevent of insertion of an insertion member, it is preferable that thereis a pedestal portion 5 to support the lower periphery of the valve 1while leaving open the center area of the rear surface of the valve 1.

The locking means is not required to have a particular limitation, aslong as it has a simple structure and locks the insertion member (suchas a syringe luer connector) at the plug body for medical fluidcontainers. For example, it may be the circular fitting hole formed atthe center of the cover 2, provided with shape and dimensions thatenable lockable fitting of the fitting hole and an insertion member suchas a luer connector. With such a structure, the insertion member can bereliably locked by a simple structure.

Furthermore, in order to perform even more reliable locking for theinsertion member, it is effective to use a lock adapter as shown in FIG.3. In FIG. 3, FIG. 3A shows a bottom view of the lock adapter, FIG. 3Bshows a side cross-sectional view of the lock adapter, and FIG. 3C,shows a side view of lock adapter.

As shown in FIG. 3, the lock adapter uses a notch portion 32 installedin the lower part of the lock adapter cap cover 31 to fasten the cover2.

More specifically, FIG. 4 shows an enlarged cross-sectional view of thelower part of a lock adapter cap cover 31, in which the notch portion 32for rotational engagement is provided on the inner side of the lockadapter cap cover 31. The lock adapter cap cover 31 is inserted as shownin FIG. 5A, so that the notch portion 32 fits with a protrusion 71,which is provided at the outer edge of the cover 2, and enables reliablefastening by locking with further rotation as shown in FIG. 5B.

Furthermore, if the insertion member is a syringe end possessing ageneral luer connector shape, it is preferable for the dimensions of thefitting hole 6 in the cover 2 to have a diameter of 3.9 to 4.4 mm, andthe edge portion of the cover 2 that is provided with the fitting hole 6to have a wall thickness of 0.3 to 2.0 mm. Also, it is preferable thatthe cover 2 has strength sufficient for it not to break even when theinsertion member is fitted firmly into the fitting hole 6. Inconsideration of such factors as medical fluid resistance and heatresistance, possible materials for this include polyacetal,polypropylene, polyethylene, polyamide, polyethylene terephthalate,polybutylene terephthalate and polycarbonate.

The valve 1 should afford easy insertion and withdrawal of the insertionmember, and reliable opening. For example, it is conceivable that theshape of the surface of the disk-shaped valve 1 is a flat shape. Also,by giving the disk-shaped valve 1 a bowl shape, the insertion member canbe inserted more easily, as well as making inadvertent withdrawal moredifficult. This also has the advantage of suppressing liquid leakagefrom the insertion hole when the insertion member is withdrawn. However,there are practical drawbacks in that residual liquids can collect onthe disk-shaped valve 1, and that such residual liquids are difficult toclear away.

Furthermore, the outward form of the valve 1 being circular, orelliptical, is convenient for forming the opening portion of thecontainer. It is convenient if the insertion hole 3 of the valve 1 is alinear slit. The material for constructing the valve 1 should be amaterial with a rubber-like elasticity, or to further limit this, amaterial with a JIS-A hardness of 20 to 55 is preferable. Specificpossible materials include silicone rubber, natural rubber, or syntheticrubbers such as butyl rubber and nitrile rubber, or thermoplasticelastomer and similar materials.

Furthermore, in order to prevent contact between the valve and medicalfluids, the plug bodies for medical fluid containers according toembodiments of the present invention are provided with a film 4 at anylocation from the rear surface of the valve to the position that can bepierced by the insertion member. If the material of the valve isselected from the group of materials consisting of vulcanized rubberssuch as silicone rubber, natural rubber, and synthetic rubbers, as wellas thermoplastic elastomer, there exists the risk of additives beingeluted out by contact between the rear surface of the valve and themedical fluids inside the container when medical fluids are stored, andthis elution can be prevented by the film 4.

Moreover, as for the material of the film 4, there are no particularrestrictions as long as it is a film capable of being pressed through byan insertion member with an obtuse tip, but it is preferable for it tohave a penetration resistance of a range not more than 30 Newtons. Thisis because it enables the film to be broken easily by pressure appliedto it by the obtuse tip of the insertion member, for which syringe luerconnectors are a typical example.

Specific examples include polypropylene-based films degraded by gammaradiation; layered plastic films whose layers have different laserabsorption, wherein portions of their resin layers have been laserprocessed to provide slits that do not pass through all the way; andlayered films of a film provided with pores that pass through all theway and a film (heat sealed layer) that maintains fluid tightness anddoes not have pores.

Furthermore, it is necessary that this film 4 does not result in piecesof ruptured film dropping when the insertion member is inserted, andpossesses the mechanical property that it can be ruptured easily. Thisis in order to prevent contamination of the medical fluid by fallenpieces of ruptured film.

Referring to the accompanying drawings, the following is an explanationof a plug body for medical fluid containers according to an embodimentof the present invention. FIG. 1 is a top plan view of the medical fluidcontainer plug body according to an embodiment of the present invention,and FIG. 2 is a cross-sectional view of the medical fluid container plugbody according to an embodiment of the present invention. In FIG. 1 andFIG. 2, numeral 1 indicates the disk-shaped valve, numeral 2 the cover,and numeral 3 the insertion hole.

FIG. 6A is a top plan view of the valve 1 of the medical fluid containerplug body according to an embodiment of the present invention, and FIG.6B is a cross-sectional view of the valve 1 of the medical fluidcontainer plug body according to an embodiment of the present invention.As shown in FIG. 6A and FIG. 6B, in addition to a ring-shaped notch 8 onits top surface, the disk-shaped valve 1 possesses a shape in which itsthickness near the center is greater than its thickness at peripheralareas. By doing so, it is possible to eliminate the difference in levelof the edge portion of the cover 2 that is provided with the fittinghole 6, and it becomes easier for medical fluids to be cleared away,etc.

Also, because the cover 2 and the pedestal portion 5 are fastening thedisk-shaped valve 1, the valve 1 is sectioned into a portion that iscompressed and a portion that is stretched by the insertion of aninsertion member such as a luer connector. Moreover, with thering-shaped notch 8 present as a starting portion on the surface of thedisk-shaped valve 1, the disk-shaped valve 1 stretches more easily. Thatis, when an insertion member is inserted in the disk-shaped valve 1, theportion of the disk-shaped valve 1 that is located further inward thanthe portion supported by the pedestal portion 5 is stretched, but theouter portion maintains its prescribed position.

Further, in this embodiment, the insertion hole 3 is in the form of asingle linear slit, but there is no particular limitation in thisregard. For example, it may also be a slit form made of threeintersecting linear slits.

Furthermore, as shown in FIG. 2, it is preferable that a pedestalprotruding portion 7 is present around the pedestal portion 5. Liquidleakage between the cover 2 and the pedestal portion 5 can be preventedby the cover 2 and the pedestal portion 5 fastening the disk-shapedvalve 1. However, if the film 4 is welded to the top surface of thepedestal portion 5 by heat sealing, unevenness in the height of thepedestal portion 5 results. Even in these circumstances, if the pedestalprotruding portion 7 is provided in a position contacting the peripheryof the disk-shaped valve 1, leakage between the pedestal protrudingportion 7 and the disk-shaped valve 1 can be prevented.

Furthermore, FIG. 7B shows a cross-sectional view of the cover 2 of themedical fluid container plug body according to an embodiment of thepresent invention, and FIG. 7A shows a bottom view of the cover 2 of themedical fluid container plug body according to an embodiment of thepresent invention.

As shown in FIG. 7A, at its center, the cover 2 has a fitting hole 6,and, as shown in FIG. 7B, a gentle taper (slant) faces toward thefitting hole 6. Also, as shown in FIG. 7A, in order for the cover 2 tobe able to easily fasten the plug body, a ring-shaped cover protrudingportion 72 is present at the lower edge of the peripheral portion of thecover 2, and, as shown in FIG. 2, is engaged with the pedestalprotruding portion 7, which is present at the periphery of the pedestalportion 5 of the plug body.

Also, it is conceivable that the cover 2 and the pedestal portion 5 arefixed together by ultrasonic welding. In this case, as shown in FIG. 13,the cover protruding portion 72 and the pedestal protruding portion 7 donot exist, and an ultrasonic-weld rib 131 is provided in a ring aroundthe upper surface of the pedestal portion 5. Additionally, by weldingthe ultrasonic-weld rib 131 with ultrasonic waves, the cover 2 and thepedestal portion 5 are welded.

Further, in this embodiment, the periphery of the cover 2 is shown ascircular, but it could also suitably be elliptical as the form of thevalve, or it could be polygonal.

By letting the cover 2 expose the center of the disk-shaped valve 1 andcover the upper periphery of disk-shaped valve 1, as well as fixedlysupport it, it is possible to reduce the externally exposed surface areaof the aperture portion of the plug body for medical fluid containers,and it is also possible to greatly decrease the opportunities for suchevents as ingress of impurities to the medical fluid inside thecontainer and infection by bacteria suspended in the air.

As for the material for cover 2, it is necessary for it to have anappropriate hardness in order to firmly hold the disk-shaped valve 1 andthe insertion member. In particular, in order for the cover 2 tofacilitate the insertion of the insertion member into the fitting hole 6(if too hard, tolerance is reduced for insertion of insertion bodies)and enable firm fittings, it is preferable that the cover 2 has anappropriate hardness and is made of a material that is difficult tobreak. For example, materials such as polyacetal, polypropylene, andpolyethylene, as well as polyamide, polyethylene terephthalate,polybutylene terephthalate, and polycarbonate are preferable.

As for the materials that constitute the valve 1, these should bematerials that exhibit ordinary rubber elasticity, or to further limitthis, a material with a JIS-A hardness of 20 to 55 is preferable.Specific possible materials include silicone rubber, natural rubber, orsynthetic rubbers such as butyl rubber and nitrile rubber, orthermoplastic elastomer and similar materials.

Furthermore, it is preferable that the wall thickness in the vicinity ofthe disk-shaped valve 1 and the insertion hole 3 is 1.0 mm to 3.2 mm.This enables a reduction of liquid leakage, and the insertion member canbe inserted easily.

Furthermore, as for the materials for the film 4, even for insertionbodies with obtuse tips such luer connectors, it is necessary that thematerial be able to be ruptured easily by the insertion of suchinsertion bodies. It is preferable that the film 4 has a penetrationresistance of not more than 30 Newtons. If it is 30 Newtons or less, thefilm can be easily broken by inserting an insertion member with anobtuse tip, for which syringe luer connectors are a typical example.Additionally, it is necessary for the surface of the film 4 that comesin contact with the medical fluid to have medical fluid resistivity.

As for films that have such penetration resistance values, it ispreferable to use films, as shown in FIG. 8B, that are provided with amultitude of non-pass-through pores. Also, as shown in FIG. 8C, the filmmay also be a layered film, having at least a film with a multitude ofpass-through pores and a film with no pass-through pores.

As for the materials of films provided with a multitude of pores,materials such as polyethylene terephthalate, polyethylene,polycarbonate, polyvinylidene chloride, and polypropylene are possible,but films that have medical fluid resistance, heat resistance, andmoisture resistance, such as polyethylene terephthalate andpolypropylene, are preferable.

Furthermore, as for the methods for providing films with a multitude ofpores, methods of forming pores by laser beam irradiation, methods inwhich, once the film is brought to its softening point, heated pinspierce the film and open holes by fusion, or methods in which heat andpressure are applied to the film by embossing rollers to open holes areconceivable.

The film without pores (heat sealed layers), is made of at least onelayer of a synthetic resin sheet that has the function of maintaining astate of being non-permeable by liquids. Also, it should have heatsealability in order to undergo heat fusion with the pedestal portion 5.

As for the material of the film without pores, polyethylene,alpha-ethylene-acrylic acid copolymers, alpha-ethylene-methacrylic acidcopolymers, ionomers, and ethylene-vinyl acetates copolymers areconceivable. In particular alpha-ethylene acrylic acid copolymers andalpha-ethylene-methacrylic acid copolymers are preferable for their highadhesive strength. High adhesive strength enables rupturing to bepropagated quickly.

As for examples of structures of the layered film that is structuredfrom film provided with a multitude of pores and film (heat sealedlayer) without pores, combinations such as stretched polypropylene thathas undergone processing for pores with non-stretched polypropylene, aswell as combinations such as polyethylene terephthalate that hasundergone processing for pores with non-stretched polypropylene, areconceivable.

An example of a particularly preferable structure is the combination ofa molecularly orientated polyethylene terephthalate that has undergoneprocessing for pores with non-stretched polypropylene. Because the layerof film that has undergone processing for pores possesses the qualitythat fissures are propagated in one direction (linear rupturing), thepossibility of ruptured film tearing off from the heat sealed portion tofall into the medical fluid and thereby contaminate it is reduced.

Furthermore, films that are made of polymer blends adjusted to thedesired penetration resistance, such as cyclic polyolefin mixed withmaterials such as polypropylene or polyethylene, are also suitable. Inthis case, blends of cyclic polyolefin mixed with polypropylene orpolyethylene in a mixing ratio of around 2:8 are preferable.

Plastic films have been enumerated above as specific examples of thefilm 4, but there is no particular limitation to these films. Forexample, although inferior in terms of disposability, a layered film inwhich one layer is aluminum foil that is easily ruptured, combined witha heat sealed layer, also would be suitable.

With this configuration, the films can be ruptured easily by thepressure of obtusely pointed objects such as luer connectors. Further,films provided with a multitude of pass-through pores, as that shown inFIG. 8A, are inappropriate because they still involve the risk ofcontact between the rear surface of the valve and the medical fluids.

Furthermore, as the film is welded only by heat sealing to the topsurface of the pedestal portion, depending on how the film ruptures,there is the risk of the medical fluid becoming contaminated by theruptured pieces of film falling into the medical fluid. Therefore, toprevent welded film from falling easily, it is possible, as shown inFIG. 9, to perform beveling 51 or the like for the inner periphery ofthe upper surface of the pedestal portion 5. By doing this, it ispossible to eliminate the sharp angle between the film 4 and thepedestal portion 5 with respect to when direct pressure is applied onthe inner periphery of the upper surface of the pedestal portion 5 byinsertion of the insertion member, and this can be expected to veryreliably prevent the falling of welded film.

Additionally, for example as shown in FIG. 10, in the event of the film4 tearing in a cross shape, it can be seen that some portion of theruptured areas will tear away from heat sealed part 101 and form tornpart 102, thus resulting in it being easier for such portions to fallinto the medical fluid. Therefore, to reduce the possibility of thiseven a little, it is desirable that the film 4 is formed as far aspossible in a way that results in almost straight-line tearing. This isbecause being torn in straight line reduces the likelihood of parts ofheat sealed part 101 being torn away and forming a torn part 102.

For this reason, by providing, for example, areas on the inner peripheryof the upper surface of the pedestal portion 5 that are beveled, andareas that are not beveled, thereby providing areas in which the film 4and the pedestal portion 5 meet at a sharp angle and areas in which theymeet at an obtuse angle, it is thus possible to control the way in whichthe film 4 tears in the event of insertion of an insertion member.

The following is a more specific explanation of examples of embodimentsof a plug body for medical fluid containers in accordance with thepresent invention.

First, polypropylene was used to produce a pedestal portion 5 providedwith a structure as that shown in FIG. 2, and then, for the film for thepedestal portion 5, two types of mixed films were heat-welded, (1) acombination of polyethylene terephthalate that had undergone processingfor pores and non-stretched polypropylene, and (2) a combination ofaligned-pore polyethylene terephthalate and non-stretched polypropylene.Each had 1,500 to 2,000 pores per square-centimeter.

Then, after welding, a disk-shaped valve 1 made of isoprene rubber wasfastened between a cover 2 made of polypropylene and the pedestalportion 5 and high-pressure steam sterilization was performed for 30minutes at 115° C. The following two experiments were performed forthese plug bodies for medical fluid containers.

First, for experiment 1, a force gauge (a “Push Pull Scale” with a fullscale of 98 Newtons manufactured by Komura Seisakusho Co., Ltd) was usedto measure the maximum load (penetration resistance) of an ordinarysyringe luer connector being thrust into the film 4 of the plug bodiesfor medical fluid containers, and both measured 24.5 Newtons. On theother hand, the maximum load (penetration resistance) when a plastic(polycarbonate-made) needle was thrust into a rubber plug body that doesnot have pass-through holes was 30 Newtons, therefore it was evidentthat for insertion bodies with obtuse tips, such as luer connections,penetration could be achieved with a lower penetration resistance thanthat of conventional plug bodies.

Next (in experiment 2), we measured the number of occurrences of foreignmatter when an ordinary syringe luer connector was thrust into the film4 of the plug bodies for medical fluid containers. In the experiment,for foreign matter that is undetectable by the human eye, we used alight-shielded type automatic particulate measurement apparatus, and forforeign matter that is detectable by the human eye, we used a capturemethod based on membrane filtering.

For the part of the experiment concerning visible foreign matter, weprepared the test system shown in FIG. 11, including a membrane filter112 (Millipore-made, 0.45 micron pore diameter, 13 mm diameter) in theplug body for medical fluid containers, and a syringe 113 filled withfiltered water. First, the syringe 113 was filled with filtered waterand then cleared of internal air bubbles. Next, the plug body formedical fluid containers was penetrated five times by an ordinarysyringe luer connector 111, then, after the filtered water insidesyringe 113 was further filled into the piece, the membrane filter 112was withdrawn and examined visually for foreign matter. The results werethat no foreign matter was confirmed for the film of either (1) or (2).

In the part of the experiment concerning foreign matter that is notdetectable by the human eye, as shown in FIG. 12, before inserting thesyringe luer connector 111, priming was performed with filtered waterinside the test system, then after clearing the test system of internalair bubbles, the system was closed. After penetrating the plug body formedical fluid containers five times with the syringe luer connector, 20ml of filtered water inside the syringe 113 was discharged through thetest system and sampled in a vial bottle 121, then the sampled filteredwater was measured for foreign matter using a light-shielded typeautomatic particulate measurement apparatus. The results were 2.9particulates per milliliter for foreign matter equal to or larger than10 microns, and 0.1 particulates per milliliter for foreign matter equalto or larger than 25 microns, thereby making it evident that asufficient standard of medical fluid quality assurance had beenachieved.

INDUSTRIAL APPLICABILITY

As shown above, the plug body for medical fluid containers of thepresent invention is able, with its film, to prevent contact between thevalve and the medical fluid, as well as enabling a reduction in thepenetration resistance for the insertion of insertion bodies with obtusetips such as those of luer connectors. Further, it is also able toprevent the medical fluid contamination that can occur when filmruptured by insertion bodies with obtuse tips falls into the medicalfluids.

1. A plug body for a medical fluid container, comprising: a disk-shapedvalve provided with an insertion hole in its central portion; and acover that fixedly supports the valve, covering at least the valve'supper periphery; wherein a lower periphery of the valve's rear surfaceis supported by a pedestal portion, a film covering the rear surface ofthe valve is arranged on an upper surface of the pedestal portion, andthe film can be pressed through by an insertion member with an obtusetip; and wherein the film is a layered film including s film providedwith a multitude of pass-through pores or slits and a film that does notinclude pores or slits.
 2. The plug body for a medical fluid containeraccording to claim 1, further comprising a locking means for locking theinsertion member to the plug body using an outer edge of the cover,which is provided with a fitting hole, when the insertion member isinserted into the insertion hole.
 3. The plug body for a medical fluidcontainer according to claim 1, wherein a peripheral portion of thepedestal portion is beveled.
 4. The plug body for medical fluidcontainers according to any of the claims 1, wherein the penetrationresistance of the film against the obtuse tip insertion member is notmore than 30 Newtons.
 5. The plug body for medical fluid containersaccording to claim 1, wherein the film, in the event of film rupturecaused by the insertion member, is ruptured linearly.
 6. The plug bodyfor medical fluid containers according to claim 1, wherein a frontsurface of the valve has a ring-shaped notch portion, which, uponinsertion of the insertion member with an obtuse tip, causes the valveto be sectioned into a portion that is fixed and a portion that expands.